Molecular characterization and alternative splicing of a MYB transcription factor gene in tumourous stem mustard and its response to abiotic stresses

作者：Wang, Weina; Sun, Quan; Cai, Chaowei; Yang, Can; Liu, Xin; He, Xiaohong; Jiang, Huaizhong; Mo, Jianchuan; Cai, Yingfan^*

来源：Biologia, 2016, 71(5): 538-546.

DOI：10.1515/biolog-2016-0066

• Brassica juncea var. tumida
• alternative splicing
• gene expression
• MYB transcription factor
• prokaryotic expression

Tumourous stem mustard, a variant of Brassica juncea (Cruciferae), is an economically important crop. In a preliminary study, the expression of a fragment of a MYB (v-myb avian myeloblastosis viral oncogene homolog) gene was screened out during stem swelling. The four complete cDNA sequences of novel MYB genes were cloned by rapid amplification of cDNA ends based on the MYB sequence fragment. These sequences, which represent distinct alternatively spliced transcripts of a BjMYB1 (Brassica juncea var. tumida Tsen et Lee MYB gene 1), possessed a similar alternative splicing pattern to several reported MYB genes of other species. RT-PCR analysis revealed different expression patterns for these four spliced transcripts in various tissues. However, stem expression of BjMYB1 gene was detected in the non-swelling growth phase, and different expression patterns were detected at other stages during stem swelling. The expression levels of the transcripts differed after treatment with various phytohormones (e.g., ABA) and NaCl. In addition, prokaryotic expression and Western blotting showed that BjMYB1-2 encodes a 5.3 kDa protein while BjMYB1-3 encodes a 21.6 kDa protein. The overexpression of BjMYB1-3 and BjMYB1-4 in Arabidopsis thaliana showed earlier germination, promoting growth and having tolerance to abiotic stress such as osmotic stress or high salt. The research of this article set the foundation for further study of the function of MYB genes in tumourous stem mustard and other Brassica plants.

• 出版日期2016-5
• 单位重庆邮电大学; 河南大学